This invention relates to surface acoustic wave devices and more particularly to a single slab SAW device that is magnetically tuned.
It is well known in the prior art that SAW devices have a fixed delay between input and output terminals which is determined by material constraints and the separation between the terminals. Variable delays with SAW devices may be caused by mechanical and electronic devices. Mechanical devices have been used to apply a stress or strain on the material forming the SAW device while electronic means may be used to change an applied electric field. Each of these functions to change the index of refraction of the SAW device which causes a delay and/or phase change in the wave traversing the SAW device.
A SAW device most nearly resembling the device of this disclosure is described in U.S. Pat. No. 4,078,186. This patented device makes use of a magnetostrictive film on a substrate which functions to vary the characteristics of the substrate.